1. Technical Field
This invention relates generally to the field of automotive catalysts for reduction of emissions from a fossil fueled internal combustion engine, and more particularly to technology for heating such catalyst by spontaneous combustion of hydrogen when exposed to the catalyst independent of any emissions.
2. Discussion of the Prior Art
A group of recently issued and related patents (U.S. Pat. Nos. 5,813,222; 5,953,908; 5,964,089; 5,845,485; and 5,964,089) disclose a method and apparatus to achieve heating of the catalyst by introducing a mixture of air and hydrogen to either the combustion chamber of the engine or to the air existing in the exhaust pipe upstream of a catalytic converter. The mixture is intended to combust within the engine to carry heat to the catalyst or spontaneously and exothermically combust when it is exposed to the catalyst. Hydrogen is supplied from a storage tank that is regularly filled with hydrogen produced on board the automotive vehicle by an electrolysis system. On-board electrolysis systems are readily known in the art as evidenced by the discussions in the above referenced patents. The systems essentially use electrical energy, derived from the vehicle's storage battery or generator, to disassociate water into its constituents, one of which is hydrogen. Care is taken to filter and purify the hydrogen to be free of any oxygen and other contaminants by reforming water with the constituent oxygen. The main body of electrolysis oxygen that is not contaminating the hydrogen is vented to atmosphere. Hydrogen is delivered to the air mixture for spontaneous combustion at a pressure of about 30-45 psig, is dispersed at flow rates of 80-200 liters per minute so that it constitutes 1-28% of the mixture. Due to the inefficiency of adding hydrogen to air at a location well upstream of the catalyst, the patents suggest adding a small electrical heater in instances where the ambient temperature conditions can be as low as -7.degree. C. (see '222 patent at column 9, lines 28-35). Such a proposal points out the shortcomings of the state of the art. Such patents also take the electrolysis oxygen and add it to the air flow when creating the combustible mixture, as the patents suggest. Unfortunately this does little to change the inefficiency of the approach.